Assembly jig



Oct. 26, 1943. w. H, ELLIS er1-AL ASSEMBLY JIG Filed Aug. 28, 1940 3.Sheets-Sheet l I NVENTORS wm.. #Md 6&0

0d. 26, 1941?. l w; H, ELLls E1-AL 2,332,625

ASSEMBLY LTIG Filed Aug. 28, 1940 3 Sheets-Sheet 2 .Frs-117 INVENTORS UM'aM/Jau@ m Oct. 26, 1943.

W. H, ELLIS ETAL ASSEMBLY .TIG

Filed Aug. 28, 1940 5 Sheets-Sheet 3 FIG 'm INVEN 'oRS GEO/PGE AP'HI/?5775 wa/AM HAMM aus AGE/V7- Paten/ted Oct. 26, 1943 4UNITED STATESPATENT? OFFICE v` ASSEMBLY JIG William Harold Ellis, El Cerrito, andGeorge Arthur Betts, Santa Monica, Calif., assgnors to Lockheed AircraftCorporation, Burbank, Calif.

Application August 28, 1940, Serial No. 354,566

' romans. k(o1. loi-288.2)

This invention relates to an improved assembly jig for aligning theIcomponent parts of quantity production units, such as airplanes orboats, during the construction thereof.

Where a number of units of one design are to be built it facilitatesconstruction and inter-` changeability of components if the unit isassembled from pre-fabricated parts or sub-assemblies in a form or jighaving locating means for the various components. It has heretofore beenthe practice to build up such a jig-or framework by Welding thepartsthereof, thus providing a permanent arrangement that can notbedisassembled for moving or storage and forms a one purpose: unit thatcannot readily -be -altered except by cutting out and scrapping theparts to be replaced. .y l

It is accordingly an object of this invention to provide a demountableand adjustable fabri eating jig or assembling fixture of thel typedescribed wherein precise location and leveling can be attained,` andreproduced should the fixture be disassembled for moving or storage.Such an` arrangement provides machined contact surfaces for memberswhich permits dismantling and reassembling, and the component parts canbe made interchangeable and stocked as standard` parts,` so vthat when ajig or fixture becomes obsolete it can-be dismantled and the variouspartsreturned to stock. Y

It is a further object off-this invention to provide an improved andsimplified jig or fixture of the class described, which embodiesadjustable ball joints and offsetable supporting heads for leveling andlocating various `components of the fixture or jig, providing precisevleveling and 1ocating of beams,` sup-ports and other members which inturn locate units of the body beingv fabricated. l e .l

It is also an object of this invention to provide an improved andsimplified jig or fixture of the class described wherein various beamsare supported on adjustable ball joints by means of hinge joints at theends of the beams so that precise leveling or angles can be set up' byusing the hinge points of the beams after theA manner of tool makerssine bars. The hinged supports for thel beams also allow' ready removaland replacement by'removing or inserting hinge pins.

It is another object of this invention to provide an. improved jig orxture ofy the type described wherein mounting points for the variouselements of the jig or xtureare universally acljustable and demountableby means `of a combined ball joint and offset mounting mem-berl whichwhen finally adjusted can be doweled to an intermediate member to retainthe precise adjustment desired, the mounting member being usable overand over again while the intermediate member can be replacedinexpensively when too many dowel holes have been drilled therein. fOther' and further'important objects of this invention will be apparentfrom the disclosures in the specification and the accompanyingA draw'ings. f

This invention in its preferred form is illustrated in the drawings andhereinafter more fully described. Y w

In the drawings: f Figure I is a side elevation of an airplane fuselageassembly jig or fixture embodying the features of thisinvention, afuselagel being outlined in dotted lines therein. Figure II is afragmentary `plan view of the of Figure I.

Figure III is an enlarged detail side elevation of one of theadjustableball joint levelingfandv locating members showing variousmeans of sup-V porting structuralor aligning beams thereon.

Figure IV is an enlarged detail correspondingv to Figure III but showingexaggerated tilting and offset adjustments thereof, i i Figure V is acentral section of the top of the j adjustable ball joint member, in thecentral plane` parallel to that of Figure IV, showing"howY the jointmember is do-weled to the intermediate member to retain the desiredprecise adjustments thereof. f

Figure VI is an end elevation of the completed jigv corresponding to theleft side of Figure I.'

'Figure VII is a transverse section taken on the line VII-VII of FigureI. f'

The embodimentv chosen' to illustrate this in.'- v'ention relates to anrairplane fuselage assem-J b'ly jig or fixture, and the outlines of anairplane fuselage 'I have beenindicated by' dotted linesV in Figures Iand II. This particular type of fixture is designed to support vlocatorsfor a series of bulkheads (not shown) and moulds formingC the shape ofthe fuselage, these bulkheads being the object to beassembled determinesthe gen-f v eral shape of the fixture, variousmembersf-there:

`doweled to the .member 2|,

of being so located as to position or support critical parts or sectionforms thereof. In the case of the illustrated fuselage, a series ofvertical posts |I are so positioned at intervals as to supporthorizontal beams I2 of convenient lengths to outline the plan profile ofthe fuselage, providing space for mounting locators (not shown) thereon,which align the various fuselage bulkheads, formers and rings and areremovable when the outer skin is to be applied at the holding points ofthe locators. The series of beams I2 are supported by adjustable balljoints I3, to be described in more detail hereinafter, the ball jointsI3 bei-ng supported by angle brackets I4 clamped to the posts I I anddoweled in their final position thereon after the beams have beenadjusted for heighth.

A series of cross-beams I5 are .supported by other ball joints I3 andangle brackets |4, near the tops of the posts I I, to support a centralhorizontal beam I6, which provides a trolley track for removing thecompleted fuselage from the jig or fixture, as Well as providingmounting or suspension points for various bulkhead locators. As shown inFigure I, a front section of the beam I6 maybe hinged to the remainingportion of the beam to be swung down into the dotted position duringconstruction of the fuselage, and swung back to its horizontal positionto clear the fuselage and serve as part of the trolley track.

An axially disposed line of short posts IB carry i ball joints I3supporting a line of beams I9 which correspond to keel supports in shipbuilding, these beams being conveniently set up at angles approximatingthe bottom outline of the fuselage, but sufficiently spaced therefrom toprovide working access to all portions of the fuselage skin; as before,temporary or removable locators supporting the various bulkheads andrings in position.

An important feature of this invention is the adjustable leveling andlocating ball joint unit hereinbefore referred to by the numeral I 3.This unit is shown in more detail in Figures III, IV andV and inconnection with the beam mounting means therefor provides an extremelyflexible set up that permits the precision adjustment of location pointsand accurate angle settings that can be subsequently reproduced shouldthe jig be knocked down for reassembly elsewhere. The ball joints I3 areformed by a pair of spaced opposed members and 2| having centralspherical recesses in their facing surfaces to receive a large ball` 22,the members being clamped about the ball by four cap screws 23 of whichopposing pairs may be oppositely adjusted to tilt the upper member 2|relative to the lower member. The lower member of the ball joint may bemounted on'angle brackets I4 clamped to the posts as previouslymentioned, or may be mounted on top a post as in Figure III. The uppermember 2| carries a dowel pad 24 having one or more dowels 25 locatingit concentric with the member 2|, the dowel locations being standardizedand duplicated more than once in the dowel pad so that after once beingused the dowel pad can be turned to a new position and rewithoutredrilling dowel holes.

A pin member 26 in turn is secured to the upper member 2| by cap screws27 passing through the dowel pads 24, the cap screws passing throughenlarged, holes in the member 26 to permit offset adjustment thereof.The member 26 carries a central pin 28 and the lateral ad- J'ustment ofthe member 26 permits accurate location of the pin 28 relative to thejig or fixture as a whole. The member 26 is predrilled for dowels 29 sothat the hole therein serves as a drill guide for drilling the dowelholes in the dowel pad after the pin'28 has been finally adjusted.

`The several beams I9 are end supported and centered on the members 26and pins 28 by means of hinge members 30 and 3| joined together byremovable hinge pins 32, the hinge axis in the members 30 beingsufficiently offset to align with one surface thereof so that bymounting Vone hinge member 30 on the pin 28 with its axis upwardlyoffset, and another on top thereof with its axis downwardly offset, theopposite hinge axes will be in horizontal alignment. The hinge members3| attached to the beam ends may be mounted up or down, as indicated oneither side of Figure II, when both are put on in the same direction theworking surfaces of the beams are aligned unlessfpurposely mounted at anangle;

Since the beams |2 and I9 support locators for various units of thefuselage it is desirable to thicken the working flange thereof, asbyfapplying an additional layer 33 of metal thereto to provide asufficient thickness to permit machining the surface thereof inalignment with the hinge pins, and to provide a sufficient Vdepth oftapped holes for the locators. Beams so prepared can have the hingemembers3| mounted thereon to support the beam with its working face 33fac-y ing up, down, or sideways, as conditions require..

While the beams may conveniently bemade of various lengths in accordancewith requirements at different locations inthe fixture; by prodesiredangle by the length between the pin axes,

and utilizing the result to determine the elevation of one pin relativeto the other. In this way the keel beams maybe set to approximate thecontour of the bottoml of the fuselage' but spaced therefromv so that aseries of stock locating members can be used to support bulkheads andother structural parts of the fuselage at their proper` locations alongthe series of beams.

An assembly jig or fixture constructed in accordance with the principlesof this invention can be rapidly, accurately, andV rigidly constructed.from standard or stock material, and after having beenassembled can betorn down andthe parts thereof returned to stock or reassembled inanother place, plant, or country, with the assurance that the originalaccuracy of assembly will be attainable. Further, any member may beremoved or swung out of the way fora particular operation, beingreturned to position thereafter.

While the illustrated embodiment of this invenplanes or quantityproduction assemblage in other and analogous fields.

Having thus described our invention land thev present preferredembodiments thereof, we desire to emphasize the fact that manymodifications may be resorted to provided they comewithinthe scope ofthe claims. Y

tive to and independently of the ball joints and f members.

2. An assembly Xture of the class described comprising a series ofmembers arranged about the outline of the object to be assembled, beamsdisposed between said members, and ball joints supported by said membersand in turn pivotally supporting adjacent ends of a pair of 4said beamsindependently of each other, said ball joints comprising upper and lowermembers, a ball, and clamping means for clamping the members about saidball, the clamping means being adjustable to Vary the angularity of theupper member relative to the lower member, and means for pivotallyattaching said beams to said ball joints whereby the beams are adaptedto be angularly adjusted relative to and independently of the balljoints and members.

3. A demountable assembly iixture ofthe type described comprising aseries of separate beams outlining and supporting the body to beassembled, ball joint supporting Vmembers connecting adjacent ends ofcontiguous beams, said ball joint supporting members including dowelplates interposed between and separately doweled lto vrela-A tivelyadjustable parts 4of the ball joint members to provide a replaceabledowel location drilling plate cooperating with iixed dowel locations inthe members on either side thereof.

4. A demountable assembly fixture of the type described comprising aseries of separate beams outlining and supporting the body to beassembled, ball joint supporting members connecting adjacent ends ofcontiguous beams, said ball joint supporting members having angularlyand laterally adjustable vertical pins, and said beams being `tted withhorizontally pivoted members fitting over the pins of the ball joints,whereby individual beams may be universally adjusted vrelative to eachother and to the common ball joint between contiguous beams.

5. An adjustable xture to rigidly support members of anv assembly jigcomprising, a base capable of rigid attachment to the assembly jig, ahead adjustably supported relative to said base byk an intervening ballelement, said head including a dowel plate, and a pin member adapted tosupport members of the assembly jigs, said dowel plate being adapted tobe rigidly attached to said pin and head members by means of dowelelements.

6. A demountable assembly xture of the type described comprising aseries of panels outlining l adjusted.

and embracing the body to ybe assembled, beams interconnecting theseveral panels, and connecting means for adjacent beam ends, including avertical pin, connecting members hingedly carried by the ends of thebeams for engagement with said vertical pin, the hinge line of saidconnecting members lying in the plane of one surface thereof wherebyadjacent beams can be mounted on a common pin with the hinge lines oftheir connections in a common plane by inverting one of saidconnections. l

7.. A demountable assembly xture of the type described comprising aseries of panels outlining and embracing th body to be assembled, beamsinterconnecting the several panels, and connecting means for adjacentbeam ends, including a vertical pin, connecting members hingedly carriedv by the ends of thebeams for engagement with said vertical pin, thehinge lines of the connecting members at opposite ends of the beamsbeing so constructed and arranged as to be usable in establishing theangles to which the beams are WILLIAMHAROLD ELLIS. GEORGE ARTHUR BETTS.

